Rotary-piston internal combustion engine



Sept. 6, 1966 J. GASSMANN ROTARY-PISTON INTERNAL COMBUSTION ENGINE 2 Sheets-5heet 1 Filed Nov. 21, 1961 FIGI INVENTOR. JOHANNES GASSMANN ATTORNEYJ.

Sept. 6, 1966 J. GASSMANN 3,270,718

ROTARY-PISTON INTERNAL COMBUSTION ENGINE Filed Nov. 21, 1961 2 Sheets-Sheet 2 INVENT OR JOHANNES GASSMANN BY MQL TT RNEY$ United States Patent Ce 1) 35,757 20 Claims. c1. 12s s The present invention relates to a rotary-piston internal combustion engine of trochoidal construction, especially with a polygonal piston carrying out a rotary movement about an eccentric arranged on the output shaft as internal envelope within an epitrochoidally-shaped housing, in which, for purposes of achieving the rotary movement, at least one trochoidally-sh-aped cam track is arranged at the housing on which the piston is guided by means of guide rollers, and in which the bearing supports of the guide rollers or the guide rollers themselves are constructed so as to be elastically yielding in the radial direction thereof as disclosed more fully in the copending application Serial No. 115,800, filed on June 8, 1961, by Johannes Gassmann and Eberhard Braun, entitled Rotary Piston Engine and assigned to the assignee of the present application, the subject matter of this copending application being incorporated herein by reference insofar as necessary.

The present invention aims at a further improvement and development of measures already broadly proposed for a play-free guidance of the piston by means of guide rollers, and essentially consists in constructing the bearing bolt on which the guide roller is supported by means of a preferably slightly arcuate floating bushing, as spring with means limiting the spring path thereof. It is possible to achieve by the use of the present invention, with relative 1y simple means, a construction of the guidance which is elastic within the required extent without, however, impairing the proper guidance by excessive elasticity.

The bearing bolt may be rigidly supported on both sides of the guide roller and may be provided with a longitudinally slo-t extending from one end face thereof to the opposite bearing place, and there may be arranged within the longitudinal slot an abutment means which limits the flexing or bending of the bearing bolt between its two bearing supports.

In order that the yieldingness takes place in the desired direction, the slot may be arranged within the bearing bolt parallel to a tangent laid adjacent the cam track. The abutment means may consist of an insert member extending nearly over the entire length of the slot which insert member fills out the slot within the area of the one bearing place of the bolt, which, however, within the area between the bearing places provides a distance to the sides of the slot.

According to another feature of the present invention, the guide roller may be supported on a bushing which is supported by a springy bearing bolt extending through the bushing and supporting thereon the bushing concentrically to the bearing places of the bearing bolt exclusively within a center area thereof, the bushing extending with both ends thereof into the bearing bore and having a diameter which is smaller than the diameter of the bearing bores.

With a guide roller which consists of an outer and of an inner sleeve, between which are arranged elastic means, the elastic means may be arranged distributed over the circumference of an annular gap formed between the outer and inner sleeve or bushing.

The elastic means may consist of clamping pins or also of cylindrical rubber parts which are inserted into bores arranged at the annular gap.

Accordingly, it is an object of the present invention to 3,270,718 Patented Sept. 6, 1966 provide a rotary-piston internal combustion engine of trochoidal construction in which the rotary piston is guided by means of guide rollers along a cam track arranged at the housing and which assures a reliable and accurate guidance of the piston substantially free of any play.

A further object of the present invention is the provision, with relatively simple means, of a yielding guidance of a rotary piston along the cam tracks provided in the housing of a rotary piston internal combustion engine of trochoidal construction which imparts a suflicient elasticity to the guidance without, however, impairing the correct guidance itself.

These and other objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein FIGURE 1 is a cross sectional view through a rotary piston internal combustion engine provided with guide means for the rotary piston in accordance with the present invention;

FIGURE 2 is a longitudinal cross sectional view, on an enlarged scale, through an elastic guide roller bearing support in accordance with the present invention for use with the guide roller arrangement of FIGURE 1;

FIGURE 3 is a longitudinal cross sectional view, on an enlarged scale, through a modified embodiment of a guide roller bearing support in accordance with the present invention also for use with the guide roller arrangement of FIGURE 1;

FIGURE 4 is an elevational view of a guide roller arrangement which is constructed elastically in the radial direction by the provision of clamping springs and which may also be used in the rotary piston internalcombustion of FIGURE 1, and

FIGURE 5 is a schematic cross sectional view, similar to FIGURE 1, through a rotary piston internal combustion engine provided with guide means in accordance with the present invention in which the guide means are supported at the housing of the cam track and arranged in the piston.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, and more particularly to FIGURE 1, the triangularly-shaped piston 2 is mounted on an eccentric (not illustrated) of the output shaft 1. The piston 2 is adapted to rotate in the direction of arrow 3 within the housing 5 provided with an internal surface forming a cam track 4 of double-arched configuration. In order to achieve a rotary movement of the piston 2 on the eccentric relative to the output shaft 1 with the necessary value of 73 of the angular velocity of the shaft for the engine illustrated in the drawing, there is arranged, instead of the known gear drive, the trochoidally-shaped cam track 6 at one housing side wall which cam track 6 cooperates with guide rollers 7 arranged at the piston 2. The guide rollers 7 are supported on bearing bolts 8 which in turn are supported on rings 9 secured to the piston 2.

As shown more fully in FIGURE 2, the guide roller 7 is supported on the bearing bolt 8 by means of the floating bushing 10 having a slightly arcuate inner diameter, whereas the bearing bolt 8 is securely arranged on both sides of the guide roller 7 within the bearings 11 of the ring 9. In order that the bearing bolt 8 acts as a spring, the bearing bolt 8 is provided with a longitudinal slot 12 which starts from one end face thereof and which extends to within the area of the opposite bearing 11. The means for limiting the spring path consist of the insert piece 13 which fills completely the slot 12 at the beginning of the slot at the one end face of the bearing bolt 8 within the area of the one bearing 11, which, however, has within the area intermediate the two bearings 11 the spacing 15 toward the two sides 14 of the slot 12. The distance 15 is determinative for the springiness of the bearing bolt 8 and therewith for the spring characteristics of the guide roller 7. If one of the sides 14 of the slot 12 abuts against the insert piece 13, then there results a limitation of the spring path. The bearing bolt 8 is securely arranged within the bearings 11 in any suitable manner. Additionally, the bearing bolt 8 is so arranged that the slot 12 is disposed parallel to a tangent with respect to the cam track 6. There is achieved by such an arrangement that the springiness of the guide roller 7 takes place during rotation of the piston 2 always substantially perpendicularly to the plane of the cam track 6.

In the embodiment illustrated in FIGURE 3, the guide roller 7 is supported on the sleeve 16 by means of a bushing 10. The sleeve 16 extends with the two ends thereof into the bores of the bearings 11 at the ring 9. The diameter of the bushing 16 is smaller than the diameter of the bores of the bearings 11. The sleeve 16 is supported within a center area of the guide roller 7 by the collar 17 of the springy bearing bolt 18 which is securely supported on both sides of the ends of the sleeve 16 with the parts 19 and 20 thereof within the bearings 11. The play 21 between the sleeve 16 and the bores of the bearings 11 is determinative for the springy bending or flexing of the bearing bolt 18. The flexing or bending of the bearing bolt 18 is limited by abutment of the sleeve 16 at the bearings 11.

The guide roller 7 illustrated in FIGURE 4 is supported by means of the bushing on the bearing bolt 22 which is constructed in an unspringy or non-elastic manner. The guide roller in this embodiment consists of an outer sleeve 23 and of an inner sleeve 24. An annular gap 25 is provided between the two sleeves 23 and 24. To assure an entrainment without relative rotary movement of the inner sleeve 24 and the outer sleeve 23, there are arranged, for the elastic construction of the guide roller, within bores 27 clamping pins 26 regularly distributed over the circumference of the annular gap 25. The clamping pins are constituted by slotted bushings on sleeves which are inserted into the corresponding bores 27 with somewhat of a pre-stress. The width of the slot of each sleeve, like clamping pin 26, is thereby determinative for the elasticity thereof. The radial size of the annular gap 25 is determinative for the elasticity of the guide roller illustrated in this embodiment. This elasticity is limited when the outer sleeve 23 abuts against the inner sleeve 24.

In the place of metallic clampin pins 26, other springy means, for example, cylindrical rubber parts may be arranged Within the bores 27.

While I have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto, but is susceptible of many changes and modifications within the spirit and scope thereof. For example, the advantages obtainable by the measures of the illustrated embodiments in which the guidance of the piston is realized by means of separate cam tracks provided within the rotary piston internal combustion engine are also attainable if the cam track itself is arranged at the piston and the guide rollers cooperating therewith are supported at the housing, as illustrated in FIGURE 5.

Thus, it is obvious that the present invention is susceptible of many changes and modifications without departing from the spirit and scope thereof, and I therefore do not wish to be limited to the details shown and described herein, but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

I claim:

1. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally-shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally-shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, and guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, bushing means for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means provided with means limiting the spring path thereof.

2. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally-shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally-shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, and said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof.

3. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said epitrochoidally shaped surface, and guide roller means for guiding the other parts along said cam track, said guide roller means efiectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said slot being arranged within said bearing bolt means substantially parallelly to a tangent at said cam track.

4. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means mating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said insert means essentially consisting of an insert member extending nearly over the entire length of said slot, said insert member substantially filling said slot within the area of the one bearing place of said bolt means while leaving a distance to the sides of said slot within the area intermediate said bearing places.

5. In a rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal surface, a polygonal piston in said housing adapted to rotate in a predetermined manner about an eccentric of the output shaft so as to slide with the piston corners along said internal surface, and trochoidally shaped cam means at one of the two parts consisting of the piston and the engine housing and guide roller means effectively providing an elastic yieldingness in the radial direction and arranged at the other of the two parts for guiding said other part along said cam means and thereby producing the said predetermined rotation of the piston, the improvement essentially consisting of a springy assembly forming each guide roller means which comprises a guide roller member, a bearing bolt, a bushing for supporting said guide roller member on said bearing bolt, and said guide roller assembly being provided with means effectively limiting the spring path thereof.

6. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including a guide roller element, springy bearing bolt means, bushing means for supporting thereon said guide roller element, said bearing bolt means being securely supported near the two ends thereof within bearing bores and extending through said bushing means, said bushing means being supported substantially concentrically to said bearing places of the bearing bolt means by said springy bearing bolt means only within a center region thereof, said bushing means extending with both ends thereof into said bearing bores and having a diameter which is smaller than the diameter of said bearing bores.

7. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movement including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, inner and outer sleeve means forming therebetween an annular gap, and elastic means distributed along the circumference and arranged within said annular gap for effectively limiting the spring path thereof.

'3. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting ot said piston means said rotary movements including at least one trochoidally-shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said epitrochoidally shaped surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, inner and outer sleeve means forming therebe tween an annular gap, and elastic means distributed along the circumference and arranged within said annular gap for effectively limiting the spring path thereof, said elastic means consisting of clamping member inserted into bores arranged at said annular gap.

9. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means and said movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, inner and outer sleeve means forming therebetween an annular gap, and elastic means distributed along the circumference and arranged within said annular gap for effectively limiting the spring path thereof, said elastic means consisting of cylindrical rubber parts inserted into bores arranged at said annular gap.

10. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness '7 in the radial direction thereof and including bolt means, floating bushing means having a slightly arcuate internal diameter for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means provided with means limiting the spring path thereof.

11. In a rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal surface, a polygonal piston in said housing adapted to rotate in a predetermined manner about an eccentric of the output shaft so as to slide with the piston corners along said internal surface, and trochoidally shaped cam means at one of the two parts consisting of the piston and the engine housing and guide roller means effectively providing an elastic yieldingness in the radial direction and arranged at the other of the two parts for guiding said other part along said cam means and thereby producing the said predetermined rotation of the piston, the improvement essentially consisting of each guide roller means comprising a guide rol-ler member, a bearing bolt constructed as springy element, a floating bushing having a slightly arched internal diameter for supporting said guide roller member on said bearing bolt, and said bearing bolt being effectively provided with means limiting the spring path thereof.

12. In a rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal surface, a polygonal piston in said housing adapted to rotate in a predetermined manner about an eccentric of the output shaft so as to slide with the piston corners along said internal surface, and trochoidally shaped cam means at one of the two parts consisting of the piston and the engine housing and guide roller means effectively providing an elastic yieldingness in the radial direction and arranged at the other of the two parts for guiding said other part along said cam means and thereby producing the said predetermined rotation of the piston, the improvement essentially consisting of each guide roller means comprising a guide roller member, a bearing bolt constructed as springy element by the provision of a longitudinal slot provided therein, a floating bushing having a slightly arched internal diameter for supporting said guide roller member on said bearing bolt, and means limiting the spring path thereof of said bearing bolt in the form of an insert piece filling said slot only in part.

13. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out the rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidal-ly shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, floating bushing means having a slightly arcuate internal diameter for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said insert means essentially consisting of an insert member extending nearly over the entire length of said slot, said insert member substantially filling said slot within the area of the one bearing place of said bolt means while leaving a distance to the sides of said slots within the area intermediate said bearing places.

14;. A rotary-piston internal combustion engine of trochoidal construction having a housing with an internal epitrochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the epitrochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to the epitrochoidally shaped surface of said housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both side of said guide roller means, floating bushing means having a slightly arcuate internal diameter for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite baering place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said slot being arranged within said bearing bolt means substantially parallelly to a tangent at said cam track, said insert means essentially consisting of an insert member extending nearly over the entire length of said slot, said insert member substantially filling said slot within the area of the one bearing place of said bolt means while leaving a distance to the sides of said slot Within the area intermediate said bearing places.

15. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said internal trochoidally shaped housing, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, bushing means for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means provided with means limiting the spring path thereof.

16. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said internal surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, and said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof.

17. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said internal surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said slot being arranged within said bearing bolt means substantially parallelly to a tangent at said cam track.

18. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, said bearing bolt means being securely supported on both sides of said guide roller means, said bearing bolt means being constructed as spring means by the provision of a slot extending substantially from one end face of said bearing bolt means to the opposite bearing place thereof and including insert means within said slot which effectively limits bending of said bolt means between the two bearing places and therewith limits the spring path thereof, said insert means essentially consisting of an insert member extending nearly over the entire length of said slot, said insert member substantially filling said slot within the area of the one bearing place of said bolt means While leaving a distance to the sides of said slot within the area intermediate said bearing places.

19. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means With the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said internal surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, inner and outer sleeve means forming therebetween an annular gap, and elastic means distributed along the circumference and arranged within said annular gap for effectively limiting the spring path thereof.

20. A rotary-piston internal combustion engine of trochoidal construction having a housing provided with an internal trochoidally shaped surface, comprising output shaft means including eccentric means, polygonal piston means adapted to carry out rotary movements about said eccentric means with the outer contour thereof approximating the internal envelope of the trochoidally shaped surface of said housing, and means for imparting to said piston means said rotary movements including at least one trochoidally shaped cam track rigid with one of the two parts consisting of said housing and piston means and bearing a predetermined relationship to said internal surface, and guide roller means for guiding the other part along said cam track, said guide roller means effectively providing an elastic yieldingness in the radial direction thereof and including bearing bolt means, floating bushing means having a slightly arcuate internal diameter for supporting said guide roller means on said bearing bolt means, said bearing bolt means being constructed as spring means provided with means limiting the spring path thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,947,290 8/1960 Froede 123-8 2,988,065 6/1961 Wankel et al 1238 FOREIGN PATENTS 1,125,876 7/1956 France.

MARK NEWMAN, Primary Examiner.

RALPH H. BRAUNER, JOSEPH H. BRANSON, JR., KARL I. ALBRECHT, RICHARD B. WILKINSON, SAMUEL LEVINE, Examiners.

F. T. SADLER, Assistant Examiner. 

1. A ROTARY-PISTON INTERNAL COMBUSTION ENGINE OF TROCHOIDAL CONSTRUCTION HAVING A HOUSING WITH AN INTERNAL EPITROCHOIDALLY SHAPED SURFACE, COMPRISING OUTPUT SHAFT MEANS INCLUDING ECCENTRIC MEANS, POLYGONAL PISTON MEANS ADAPTED TO CARRY OUT ROTARY MOVEMENTS ABOUT SAID ECCENTRIC MEANS WITH THE OUTER CONTOUR THEREOF APPROXIMATING THE INTERNAL ENVELOPE OF THE EPITROCHOIDALLY-SHAPED SURFACE OF SAID HOUSING, AND MEANS FOR IMPARTING TO SAID PISTON MEANS SAID ROTARY MOVEMENTS INCLUDING AT LEAST ONE TROCHOIDALLY-SHAPED CAM TRACK RIGID WITH ONE OF THE TWO PARTS CONSISTING OF SAID HOUSING AND PISTONS MEANS AND BEARING A PREDETERMINED RELATIONSHIP TO THE EPITROCHOIDALLY SHAPED SURFACE OF SAID HOUSING, AND GUIDE ROLLER MEANS FOR GUIDING THE OTHER PART ALONG SAID CAM TRACK, AND GUIDE ROLLER MEANS EFFECTIVELY PROVIDING AN ELASTIC YIELDINGNESS IN THE RADIAL DIRECTION THEREOF AND INCLUDING BEARING BOLT MEANS, BUSHING MEANS FOR SUPPORTING SAID GUIDE ROLLER MEANS ON SAID BEARING BOLT MEANS, SAID BEARING BOLT MEANS BEING CONSTRUCTED AS SPRING MEANS PROVIDED WITH MEANS LIMITING THE SPRING PATH THEROF. 